There are a lot of rotary tools on the market but I chose this one for the battery system. Many tools share the M12 battery in my shop.. You can buy M12 Replacement Batteries to save some money but I would not recommend the knock-off tools. I added the Dremel EZ Lock chuck to this to make it easier to change the cut-off wheels. Warning, the quick change wheels seem to wobble at the higher speeds on this rotary tool.